Technology and Social Change
Lecture 3: Ancient Societies and Technology
Part 1: Motivating Puzzles & Learning Objectives
Why Did Ancient Societies Rarely Experience Sustained Growth?
Rome had concrete, roads, aqueducts—then centuries of stagnation
China invented paper, printing, and gunpowder—yet no industrial revolution
Mesopotamia created writing, mathematics, law—empires still collapsed
For ~10,000 years, most humans lived near subsistence
The “modern breakthrough” is only ~250 years old
FIGURE 1 — The Long Stagnation: GDP Per Capita Over 10,000 Years
FIGURE 2 — Population Growth: Another Perspective on Stagnation
Guiding Questions
How did political institutions emerge from egalitarian forager bands?
Why do some societies innovate while others suppress new technologies?
What role do factor prices play in directing technological change?
Can we predict which societies develop growth-promoting institutions?
Learning Objectives
By the end of this lecture, you should be able to:
Define “institutions” and distinguish formal vs informal constraints (North 1990)
Explain Boix’s producer–looter model of state formation (Boix 2015)
Apply Allen’s induced innovation hypothesis to historical cases (Allen 2009)
Compare Mesopotamia, Rome, and Han China through the Boix–Allen lens
Evaluate critiques and propose empirical tests
Roadmap
Part 1: Motivation & objectives
Part 2: Core theoretical framework (Boix + Allen + North)
Part 3: Comparative evidence (Mesopotamia, Rome, Han China)
Part 4: Critiques, alternatives, discussion
Part 2: Core Theoretical Framework
What Are Institutions? (Douglass North 1990)
“Humanly devised constraints that structure political, economic, and social interaction”
Formal rules: constitutions, laws, property rights
Informal constraints: customs, traditions, norms, taboos
Enforcement: courts, social sanctions, reputation
Institutions reduce uncertainty and transaction costs
Two Institutional Archetypes (Acemoglu & Robinson 2012)
Inclusive
Broad property-rights protection
Participation and contestation
Rewards innovation (“creative destruction”)
Extractive
Power concentrated in elites
Extraction from many to few
Suppresses creative destruction → stagnation
The Boix Model: Producers vs. Looters (Boix 2015)
Forager societies: relatively egalitarian, mobile, low storage
Agriculture creates localized productivity clusters (spatial inequality)
New surplus becomes storable and defensible
Two strategies emerge: produce or loot
State emerges as protection racket or coordination device (depending on bargaining)
FIGURE 3 — The Boix Producer-Looter Model
┌─────────────────────────────────────────────────────────────────────────────┐
│ THE PRODUCER-LOOTER MODEL (Boix 2015) │
└─────────────────────────────────────────────────────────────────────────────┘
PRE-AGRICULTURE POST-AGRICULTURE
═══════════════ ════════════════
RESOURCES: Mobile, dispersed Fixed, concentrated
(game, gathered plants) (stored grain, herds)
STORAGE: Minimal Substantial
(spoilage, transport) (granaries)
DEFENSIBILITY: Low High
(resources move) (land is fixed)
│ │
▼ ▼
PREDATION LOW PAYOFF HIGH PAYOFF
INCENTIVE: • Hard to find • Easy to find
• Hard to take • Worth defending
• Little to take • Much to take
│ │
▼ ▼
SOCIAL EGALITARIAN STRATIFIED
STRUCTURE: • Sharing norms • Elites emerge
• Low hierarchy • Exit costs high
│ │
▼ ▼
STATE MINIMAL EMERGES
FORMATION: • No surplus to tax • Protection racket
• OR coordination
KEY INSIGHT: Agriculture changed the PAYOFF STRUCTURE, not human nature.FIGURE 4 — Archaeological Evidence: Heights as Inequality Proxy
The Boix Causal Chain
Geography/Climate → Agricultural potential
Agricultural potential → Spatial concentration of productivity
Concentration → Producer–looter dynamics
Dynamics → State formation + institutional type
Institutions → Innovation incentives → Economic performance
FIGURE 5 — Boix Causal DAG: From Geography to Development
Boix causal framework: geography operates through institutions, not directly
Factor Prices and the Direction of Innovation (Robert Allen 2009)
Innovation is not random: it responds to incentives
Inventors/firms economize on expensive factors
High wages → labor-saving innovation
Cheap energy → energy-intensive production becomes viable
Factor prices shaped by geography, institutions, and trade
FIGURE 6 — Allen’s Induced Innovation Mechanism
┌─────────────────────────────────────────────────────────────────────────────┐
│ INDUCED INNOVATION HYPOTHESIS (Allen 2009) │
└─────────────────────────────────────────────────────────────────────────────┘
RELATIVE FACTOR PRICES
│
┌────────────────┼────────────────┐
▼ ▼ ▼
┌───────────┐ ┌───────────┐ ┌───────────┐
│ LABOR │ │ CAPITAL │ │ ENERGY │
│ (wages) │ │ (interest│ │ (fuel) │
│ │ │ rates) │ │ │
└─────┬─────┘ └─────┬─────┘ └─────┬─────┘
└────────────────┼────────────────┘
│
▼
┌────────────────────────┐
│ INNOVATION DIRECTION │
│ │
│ Economize on EXPENSIVE │
│ factors by substituting│
│ CHEAP factors │
└────────────┬───────────┘
│
┌──────────────────┼──────────────────┐
▼ ▼ ▼
┌────────────────┐ ┌────────────────┐ ┌────────────────┐
│ IF LABOR HIGH: │ │ IF CAPITAL │ │ IF ENERGY │
│ Labor-saving │ │ HIGH: │ │ HIGH: │
│ machines │ │ Labor-intensive│ │ Energy-saving │
│ (Britain 1800) │ │ production │ │ technologies │
└────────────────┘ └────────────────┘ └────────────────┘
KEY INSIGHT: Same technology may be RATIONAL in one context and IRRATIONAL
in another—depending on factor prices.Allen’s High-Wage Economy Thesis
Britain had uniquely high wages relative to capital and energy
Coal abundant and cheap → energy-intensive mechanization profitable
High wages made labor-saving machinery worth developing
In low-wage societies, same machines often unprofitable
Synthesizing Boix and Allen
Boix: institutions emerge from material conditions + bargaining
Allen: factor prices direct technological change
Synthesis: Institutions → Factor prices → Innovation direction → Growth
Extractive institutions distort signals (forced labor, slavery, heavy extraction)
Inclusive institutions allow market-determined prices → stronger innovation incentives
FIGURE 7 — Integrating Boix and Allen
┌─────────────────────────────────────────────────────────────────────────────┐
│ INTEGRATED FRAMEWORK: BOIX + ALLEN │
└─────────────────────────────────────────────────────────────────────────────┘
┌─────────────┐ ┌─────────────┐ ┌─────────────┐
│ GEOGRAPHY │────────▶│ AGRICULTURAL│────────▶│ PRODUCER- │
│ & CLIMATE │ │ POTENTIAL │ │ LOOTER │
└─────────────┘ └─────────────┘ └──────┬──────┘
│
BOIX'S FRAMEWORK │
═══════════════════════════════════════════════╪═══════════════
▼
┌─────────────┐
│INSTITUTIONS │
│ (type) │
└──────┬──────┘
│
┌──────────────────────┼──────────────────────┐
▼ ▼ ▼
┌───────────┐ ┌───────────┐ ┌───────────┐
│ LABOR │ │ PROPERTY │ │ MARKET │
│ SYSTEMS │ │ RIGHTS │ │ ACCESS │
│ Slavery? │ │ Secure? │ │ Open? │
└─────┬─────┘ └─────┬─────┘ └─────┬─────┘
└──────────────────────┼──────────────────────┘
│
═══════════════════════════════════════════════════════════════════════
ALLEN'S FRAMEWORK │
▼
┌─────────────┐
│ FACTOR │
│ PRICES │
└──────┬──────┘
▼
┌─────────────┐
│ INNOVATION │
│ DIRECTION │
└──────┬──────┘
▼
┌─────────────┐
│ ECONOMIC │
│ PERFORMANCE │
└─────────────┘
KEY: Extractive institutions + cheap/coerced labor → weak mechanization incentivesState Capacity: Necessary but Not Sufficient
States can promote innovation: infrastructure, property rights, public goods
States can suppress innovation: taxation, regulation, extraction
High capacity + inclusive institutions → growth
High capacity + extractive institutions → sophisticated extraction
Low capacity → limited ability to do either
Vocabulary Check
Institutions: rules of the game (North 1990)
Extractive: power concentrated; extraction from many to few (Acemoglu & Robinson 2012)
Inclusive: broad participation; protected property rights (Acemoglu & Robinson 2012)
Induced innovation: technology responds to relative factor prices (Allen 2009)
State capacity: ability to implement policy, collect taxes, project power
Part 3: Comparative Evidence and Cases
Three Ancient Societies, Three Paths
Mesopotamia: early state formation; cycles of centralization/collapse
Rome: engineering prowess; institutional sophistication; eventual stagnation
Han China: bureaucratic state; sustained innovation; different trajectory
Same broad era—different geographies and outcomes
What explains the variation?
FIGURE 8 — Three Societies Compared: Overview
┌─────────────────────────────────────────────────────────────────────────────┐
│ THREE ANCIENT SOCIETIES: OVERVIEW │
└─────────────────────────────────────────────────────────────────────────────┘
MESOPOTAMIA ROME HAN CHINA
(~3500-500 BCE) (509 BCE-476 CE) (206 BCE-220 CE)
GEOGRAPHY River valleys Mediterranean Plains + rivers
Tigris/Euphrates Italy → empire Yellow/Yangzi
CORE Temple → Palace Republic → Empire Central bureaucracy
INSTITUTIONS Cycles of unity/ Increasingly Merit elements
fragmentation extractive Confucian ideology
LABOR Corvée + slavery Massive slavery Peasantry + corvée
REGIME State-controlled Conquest → slaves Free farmers primary
INNOVATION Writing, math Engineering Paper, iron casting
Irrigation tech Roads, concrete Agricultural tech
State-directed Elite consumption State-promoted
OUTCOME Cycles of rise/fall Rise then decline Long stability
No breakthrough No breakthrough No breakthrough
PUZZLE: Different paths, same stagnation outcome. Why?Mesopotamia: Between the Rivers
Tigris and Euphrates: unpredictable flooding
Irrigation required collective action and central coordination
High agricultural productivity concentration
Surrounded by pastoral/nomadic populations (potential looters)
Classic Boix setup: productive clusters vulnerable to predation
Mesopotamian Institutions and Innovation
Temple economy → Palace-centered kingship (lugal)
Cycles: city autonomy → empire → collapse → repeat
Hammurabi’s Code: contracts, property, standardized punishment
Innovation: writing (cuneiform), mathematics, metallurgy, irrigation
Key pattern: innovation primarily state-directed (bureaucratic needs)
Rome: From Republic to Empire
Early Republic: relatively inclusive (for citizens); checks on power
Expansion → slaves + wealth concentration + land consolidation
Empire: increasingly extractive; weaker protections for non-elites
High capacity persists for centuries
Late Empire: administrative strain, fragmentation
The Roman Paradox
Engineering feats: aqueducts, roads, concrete, heating systems
Agricultural improvements: plows, presses, storage
Dense trade networks across the Mediterranean
Yet: limited labor-saving mechanization
Per-capita income stagnates then declines
Why Rome Didn’t Mechanize (Allen’s Logic)
Massive slavery → very cheap labor
Allen: cheap labor → low returns to labor-saving machinery
Estimates suggest up to 30% of Italy’s population were slaves at peak (scholars debate exact figures)
Why build a water mill when slaves can grind grain cheaply?
Elite preferences (“disdain for mechanical arts”) may reinforce, but incentives came first
FIGURE 9 — Factor Prices: Rome vs. Medieval Europe
Lower labor costs reduce incentives for labor-saving mechanization
Source: Conceptual illustration based on Allen (2009)
Han China: Bureaucratic Capacity
Unified empire with sophisticated bureaucracy
Meritocratic elements (exam system emerges over time)
State investment in infrastructure: roads, canals, frontier defense
Confucian ideology: stability, hierarchy, education
More nuanced than simple extractive/inclusive binary
Chinese Innovation Under the Han
Paper (~100 CE): transforms bureaucracy and education
Iron casting: often superior to Roman wrought iron
Agricultural tech: iron plows, rotation improvements
Water control: large canal systems
Yet China also didn’t industrialize—why?
The Needham Question
Joseph Needham (Science and Civilisation in China, 1954–): why no Chinese Industrial Revolution?
Institutional hypothesis: exam system, unified empire, limited interstate competition
Factor-price hypothesis (Allen): abundant labor → weak mechanization incentives
Geographic hypothesis (Pomeranz): coal in “wrong” place; no “ghost acreages”
No consensus—active scholarly debate continues
Common Pattern Across Cases
Despite different paths, all three reached similar stagnation outcome
Mesopotamia: extractive temple/palace economies + coerced labor
Rome: massive slavery → suppressed wages → weak mechanization incentives
China: abundant labor + institutional barriers to diffusion
Framework explains both achievements AND limits
Setting Up the Modern Breakthrough
Pre-modern world: limited sustained per-capita growth is the norm
Medieval Europe: fragmentation + rising wages + cheap energy in places
Industrial Revolution emerges from a rare combination
Allen: Britain’s factor prices made mechanization profitable
Long-run takeaway: geography, institutions, and factor prices interact
Path Dependence and Institutional Lock-In
Institutions persist: elites defend equilibria that benefit them
Extractive institutions create beneficiaries who block change
Change requires shifting bargaining power, often via shocks
“Critical junctures” (war, plague, revolution) can open windows for reform
What Have We Learned from the Cases?
Geography shapes initial conditions but not final outcomes deterministically
Institutions emerge from bargaining, not pure efficiency
Cheap labor undermines mechanization incentives (Allen mechanism)
State capacity can serve growth or extraction
Similar “stagnation” endpoint can arise via different pathways
Part 4: Critiques, Alternatives, and Discussion
Critique #1: Geographic Determinism?
Critique: Boix overweights geography
If geography → institutions → outcomes, is geography destiny?
Response: geography shapes parameters, not outcomes
Same geography can yield different institutions (contingency matters)
But: contingency may be underspecified
Critique #2: Culture and Ideas
Mokyr (2016): Enlightenment ideas enabled sustained innovation (“culture of growth”)
Weber (1905): ethics/values shaped capitalism
Critique: Boix/Allen too materialist
Counter: culture may be shaped by material incentives
Did Romans disdain mechanics because of culture, or did cheap slaves make mechanics economically irrelevant?
Critique #3: Reverse Causation (Endogeneity)
Do institutions cause growth—or does growth enable inclusive institutions?
Selection bias: successful cases get more attention
Need exogenous variation to claim causality
Colonial institutions as quasi-natural experiment (Acemoglu et al. 2001)
Critique #4: Oversimplification
Extractive/inclusive can be too binary
China: bureaucratic + meritocratic elements (hybrid)
Rome: varies over time and region
Need richer typologies for institutions and innovation regimes
What Would Change My Mind? (Falsifiers)
Sustained growth under clearly extractive institutions (without catching-up logic)
Stagnation despite inclusive institutions and “good” factor prices
Cultural change repeatedly preceding material change (robustly)
Successful institutional reform that ignores factor-price context
Archaeological evidence contradicting inequality–agriculture link
Discussion Questions
Can institutions be reformed by design, or must material conditions shift first?
Is the US today more extractive or inclusive than in 1950? Why?
What would Boix/Allen predict about AI and automation effects?
Are there “developmental states” that contradict this framework?
How should ancient history inform modern development policy?
More to Consider
If slavery explains Rome’s stagnation, why did the antebellum US South innovate at all?
Does China’s recent growth contradict Acemoglu & Robinson?
Would an industrial revolution have happened “somewhere” eventually?
What role do small-scale institutions (firms, guilds) play?
How should we weight structural vs. contingent factors?
Key Readings
Boix, C. (2015) Political Order and Inequality, Ch. 1–4
Allen, R.C. (2011) Global Economic History: A Very Short Introduction
Allen, R.C. (2009) The British Industrial Revolution in Global Perspective
Acemoglu, D. & Robinson, J.A. (2012) Why Nations Fail, Ch. 1–2
North, D.C. (1990) Institutions, Institutional Change, and Economic Performance
Extended Reading List
North, Wallis & Weingast (2009) — Limited vs open access orders
Scheidel, W. (2019) — Escape from Rome; empire as innovation suppressor
Mokyr, J. (2016) — A Culture of Growth; ideas as key driver
Pomeranz, K. (2000) — The Great Divergence; late/contingent divergence
Tilly, C. (1990) — Coercion, Capital, and European States
Scott, J.C. (2017) — Against the Grain; early states as extraction
Popescu (TEC) Technology & Social Change Lecture 3: Ancient Societies and Technology